This invention is directed generally to a conveyor for conveying materials. In one aspect, the invention relates to a device and method for conveying materials without accumulating a product build up on a conveying surface due to friction that opposes a conveying motion. In another aspect, the invention relates to a device and method for conveying materials without storing an electrical charge that is produced on the conveyor as a result of an interaction between the surface of the conveyor and the materials being conveyed, thus producing a conveying surface that exhibits substantially improved release characteristics. In yet another aspect, the invention relates to a conveyor which is a trough made substantially of an ultra-high-molecular-weight material. In yet a further aspect, the invention relates to a conveyor which is fixedly secured to at least one position and able to move in a predetermined direction at other positions.
Conveying systems are widely used in many settings to transport products from one location to another. Horizontal motion conveyors have been used in such instances, and in particular, have been used in the conveying of food products. Due to the substantially horizontal motion generated by horizontal motion conveyors, products are less likely to incur damages as they are conveyed on horizontal motion conveyors. Thus, because of their quality preserving characteristics, horizontal motion conveyors are used in food handling and food conveying environments, as well as other settings.
However, conventional horizontal motion conveyors are also susceptible to clogging. That is, the conveying surfaces of conventional horizontal motion conveyors are generally formed of carbon or stainless steel, and these materials generally exhibit a high coefficient of friction. Thus, as a product is conveyed along a conveying surface, residue from pieces of the product can remain on the conveying surface and can lead to an undesirable product build-up on the conveying surface. In a case of conveying a product with a tendency to adhere to a conveying surface, the conveying path of the horizontal motion conveyor can become clogged due to residual build up, resulting in restricted movement of the products being conveyed.
To overcome these problems, conveying systems using anti-static material linings positioned on a surface portion of the conveyors have been developed. Conventional uses of the anti-static material include securing sectional pieces of the anti-static material linings to surface portions of a conveyor in order to combat the adherence of a product being conveyed to the surface of the conveyor. Accordingly, the anti-static material lining that is attached to the surfaces of the conveyor interacts with the product being conveyed. This minimizes residual accumulation of the product on the surface of the conveyor.
However, the arrangements for securing the anti-static material linings to the surfaces of conveyors have contributed to unsanitary conditions of conveyors, and have compromised the quality of the products that are conveyed on the conveyors. In particular, due to the use of sectioned pieces of the anti-static material linings that attach to the surfaces of the conveyor, contact gaps occur at the edges of the anti-static material linings between the surface of the conveyor and the anti-static material linings, as well as at positions where a plurality of pieces of the anti-static material linings abut.
Contact gaps can also occur around openings that are formed through a floor portion of the conveyor. Such openings are generally regulated by the opening and closing of a gate, which controls the discharge of materials from the conveyor at intermediate positions along the conveying path.
The contact gaps can accumulate undesirable material. For example, food, moisture, and other materials that remain trapped in the contact gaps can degrade the sanitary conditions of the conveyor, and accordingly, the conveyor requires repeated attention and cleaning Moreover, in the case of a conveyor with a gate formed in a bottom portion, the contact gaps can lead to production problems when the product flow is not accurately controlled due to leaking or restricted product flow.
Although attempts have been made to seal the contact gaps created by the anti-static material linings that are attached to the surfaces of conveyors, these attempts have been unreliable, and sanitary conditions remain questionable. Therefore, contact gaps created when anti-static material linings are attached to a surface of a conveyor require constant monitoring and cleaning.
In addition, the properties of some anti-static materials have made their use difficult in conveying systems. For example, an ultra-high-molecular-weight (UHMW) material, has a very high rate of thermal expansion, and thus, UHMW material is very sensitive to changes in environmental conditions, and in particular, very sensitive to changes in temperature. The UHMW material""s high sensitivity to temperature changes has hindered the integration of UHMW material into more conveying settings, as temperature fluctuations, including warm and high temperatures, are frequently encountered in such environments.
Thus, there exists a need for a conveyor that provides conveying surface which can resist friction and can provide good static-dissipating characteristics, while satisfying sanitation requirements and quality standards. Further, there exists a need for a conveyor that utilizes the release characteristics of UHMW material and accommodates the expansion and contraction in the UHMW material due to changes in temperature. A need further exists for a conveyor that provides good static-dissipating qualities and greatly eliminates contact gaps in a conveyor using the UHMW material. There also exists a need for a conveyor that eliminates the contact gaps between a bottom opening in a conveyor and a gate formed at the opening to regulate the flow of a product through the opening.
The present invention is a new and advantageous device and method for conveying a product on a surface that can efficiently resist a frictional force in a direction opposite to a conveying direction and can dissipate an electrical charge created by an interaction between the conveying surface and a product being conveyed, thus decreasing the likelihood of clogging the conveyor. The conveying assembly meets sanitary requirements by greatly reducing the occurrences of contact gaps throughout the conveying assembly, thereby minimizing maintenance and cleaning requirements, as well as product leakage.
According to one aspect of the invention, a conveying system comprises a conveying member which has friction resistant properties, a support structure for supporting the conveying member, and a driving unit attached to the support structure for generating a conveying motion. The conveying system is provided with at least one securing member for rigidly securing the conveying member to the support structure, and at least one biasing member for allowing relative movement between the conveying member and the support structure along a first axis and for preventing relative movement between the conveying member and the support structure in any direction other than along the first axis. The driving unit produces a conveying motion in the conveying member in order to advance the materials being conveyed along the conveying member in the conveying direction.
According to another aspect of the invention, a conveying member for a conveying system includes a bottom portion on which materials are conveyed during a conveying operation and at least one wall portion for retaining the materials on the bottom portion during the conveying operation. The conveying member consists primarily of a material having friction resistant properties.
According to yet another aspect of the invention, a conveying assembly comprises a conveying system, which includes a conveying member that consists primarily of a material having friction resistant properties, and a support structure for supporting the conveying member. The conveying member is rigidly secured to the support structure by at least one securing member, and is further provided with at least one biasing member for allowing relative movement between the conveying member and the support structure along a first axis and for preventing relative movement between the conveying member and the support structure in any direction other than along the first axis.
According to one aspect, the present invention provides a conveying system that utilizes the self-lubricating aspects of ultra-high-molecular-weight material in order to more efficiently convey a product without generating a product build up on a conveying surface.
According to yet another aspect of the invention, a method of conveying materials along a conveying member includes providing a conveying member having anti-static properties, and producing a conveying motion in the conveying member to advance the materials along the conveying member in the conveying direction.